Composition, its process of polymerization, its use, an object obtained following polymerization of composition and recycling

Abstract

The present invention relates to a composition for preparing polymers comprising a precursor or a prepolymer for thermosetting polymers. In particular the present invention relates to a recyclable composition comprising a thermoset polymer, its process of polymerization, and an object obtained, as well as a recycling process. The present invention also relates to a process for manufacturing thermoplastic composites, mechanical parts or structural elements made of composite material and to mechanical parts or structural elements made of composite material obtained via the process using such a composition comprising a precursor or a prepolymer for thermosetting polymers and a process for recycling.

Description

COMPOSITION, ITS PROCESS OF POLYMERIZATION, ITS USE , AN OBJECTOBTAINED FOLLOWING POLYMERIZATION OF COMPOSITION AND RECYCLING[Field of the invention]

[0001] The present invention relates to a composition for preparing polymers comprising a precursor or a prepolymer for thermosetting polymers .

[0002] In particular the present invention relates to a recyclable composition comprising a thermoset polymer, its process of polymerization, and an obj ect obtained, as well as a recycling process .

[0003] The present invention also relates to a process for manufacturing thermoplastic composites , mechanical parts or structural elements made of composite material and to mechanical parts or structural elements made of composite material obtained via the process using such a composition comprising a precursor or a prepolymer for thermosetting polymers and a process for recycling .[Prior art]

[0004] Thermoset polymers are materials that are widely used today in several fields and applications , for example in the construction, aeronautic, automobile or railway sectors , where they are part of mechanical parts .

[0005] These mechanical parts that have to withstand high stresses during their use are widely manufactured from composite materials . A composite material is a macroscopic combination of two or more immiscible materials . The composite material consists of at least one material which forms the matrix, i . e . a continuous phase that ensures the cohesion of the structure , and a reinforcing material .

[0006] The purpose of using a composite material is to obtain performance qualities that are not available from each of its constituents when they are used separately . Consequently, composite materials are widely used in several industrial sectors , for instance building, automotive , aerospace , transport , leisure , electronics , and sports notably due to their better mechanicalperformance (higher tensile strength, higher tensile modulus , higher fracture toughness ) and their low density, in comparison with homogeneous materials .

[0007] However recycling of thermoset materials can be very difficult or is not efficient or even sometimes nearly impossible . Often the product is grinded to small powders , which are used as fillers , or not recycled at all as for example epoxy resin based composite wind blades which are stocked in landfills or thermoset based composites are incinerated .

[0008] As thermoset polymers are highly crosslinked during the curing step they cannot be remelted or reprocessed . Consequently, they cannot be recycled as thermoplastic polymers , which can be either depolymerized for recovering the respective monomers or retransformed by for example granulating the article or obj ect to be recycled thermoplastic polymer followed by re-inj ection or reextrusion .

[0009] Chemical recycling is not easy and if requires very specific monomers or crosslinkers in the thermosetting polymer in order to hydrolyse or for decrosslinking . Or in the case of thermoset polymeric composites if the interest is only in the fiber part the chemical recycling requires specific (harmful ) solvents .

[0010] In cases of recycling of thermoset polymeric composites where only the fiber part is recovered, the recycling can also be thermal by pyrolysis or fluidized bed technologies .[Oil ] The document WO2023 / 174747 discloses ground composite materials that are used in curable epoxy compositions . The composite material is either comprising unsaturated polyester resin or cured epoxy resin . The ground material has a particle size distribution that is well below 1mm, even below 500pm.

[0012] The document W02018 / 006090 discloses methods of reshaping and recycling thermoset polymers and composites containing thermoset polymers . The methods involve the bond exchange reaction of exchangeable covalent bonds in the polymer matrix with a suitable small molecule solvent in the presence of a catalyst .

[0013] The document WO2022 / 238128 discloses (meth) acrylate based reactive diluent composition for unsaturated polyester resins . Thedocument substitutes the styrene unsaturated polyester resins by (meth ) acrylic acid ester monomer . However the composition does not comprise a (meth) acrylic polymer

[0014] The document WO2013 / 124273 discloses a thermosetting resin composition comprising an unsaturated polyester resin, ethylenically unsaturated compounds , benzyl methacrylate and methacrylate containing resin, latter being a reaction product of an epoxy oligomer or polymer with methacrylic acid or methacrylamide . The composition does not comprise a (meth ) acrylic polymer .

[0015] The document JP2007 / 291179 discloses a curable resin composition comprising an unsaturated polyester , a monofunctional (meth ) acrylate monomer and a thickening agent .

[0016] It is not disclosed or suggested in any of these documents that a composition comprising the four components ( al ) a (meth ) acrylic polymer ( Pl ) , ( a2 ) a (meth) acrylic monomer (Ml ) , an unsaturated polyesters (UP1 ) or a vinyl ester resin (VE1 ) and a monomer (M2 ) in the respective ranges , yields to a recyclable thermoset polymer comprising composition or a recyclable thermoset polymer comprising composite or article .[TECHNICAL PROBLEM]

[0017] The aim of the invention is thus to remedy at least one of the drawbacks of the prior art .

[0018] An obj ective of the present invention is to have a composition comprising a precursor of a thermoset polymer , which once the composition is polymerized, it can be recycled or easier recycled, including the polymeric part .

[0019] An obj ective of the present invention is also to have a method to recycle a polymer composition or a polymeric article or a polymeric composite , that comprises a thermoset polymer .

[0020] Another obj ective of the present invention is to use a composition comprising a prepolymer or precursor of a thermoset polymer to make an easier recyclable polymer composition or a polymeric article or a polymeric composite comprising a thermoset polymer .

[0021] Still another objective of the present invention is to propose a composition for preparing thermoset polymer comprising compositions or polymeric thermoset comprising composites and a method of recycling such thermoset polymer comprising compositions or polymeric thermoset polymer comprising composites.

[0022] Still another objective of the present invention is to propose a composition for preparing thermoset polymer comprising compositions or polymeric thermoset comprising composites for a faster method of recycling such thermoset polymer comprising compositions or polymeric thermoset polymer comprising composites.[BRIEF DESCRIPTION OF THE INVENTION]

[0023] It has been discovered that a liquid composition (LC1) comprising :(a) 100 parts by weight of a liquid (meth) acrylic composition (MCI) comprising:(ai) from 10% by weight to 50% by weight of one or more(meth) acrylic polymers (Pl) , and(a2) from 50% by weight to 90% by weight of one or more(meth) acrylic monomers (Ml) , each monomer (Ml) comprising only one (meth) acrylic function per monomer,(b) from 50 parts by weight to 150 parts by weight of composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) comprising:(bi) from 40% by weight to 80% by weight of one or more unsaturated polyesters (UP1) or a vinyl ester resin (VE1) , and (bi) from 20% by weight to 60% by weight of one or more monomers (M2 ) ,(c) optionally from 0.01 part by weight to 7 parts by weight of a polymerization initiator (INI1) ,(d) optionally between lOOppm and 20000ppm of an accelerator, allows to provide a composition comprising a precursor of a thermoset polymer, which once the composition is polymerized, it can be recycled or easier recycled in comparison to a composition not comprising the (meth) acrylic composition (MCI) .

[0024] It has also been discovered that a liquid composition (LC1) comprising :(a) 100 parts by weight of a liquid (meth) acrylic composition (MCI) comprising:(ai) from 10% by weight to 50% by weight of one or more(meth) acrylic polymers (Pl) , and(a2) from 50% by weight to 90% by weight of one or more(meth) acrylic monomers (Ml) , each monomer (Ml) comprising only one (meth) acrylic function per monomer,(b) from 50 parts by weight to 150 parts by weight of composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) comprising:(bi) from 40% by weight to 80% by weight of one or more unsaturated polyesters (UP1) or a vinyl ester resin (VE1) , and (b2) from 20% by weight to 60% by weight of one or more monomers (M2 ) ,(c) from 0.01 part by weight to 7 parts by weight of a polymerization initiator (INI1) ,(d) between lOOppm and 20000ppm of an accelerator, and(e) optionally a thixotropic agent, allows to provide a composition comprising a precursor of a thermoset polymer, which once the composition is polymerized, it can be recycled or easier recycled in comparison to a composition not comprising the (meth) acrylic composition (MCI) .

[0025] It has been discovered as well that process for manufacturing composites, preferably thermoset polymer comprising composites (TPCO) , said process comprising the following steps: i) impregnating fibres or a fibrous material with a liquid composition (LC1) comprising:(a) 100 parts by weight of a liquid (meth) acrylic composition (MCI) comprising:(ai) from 10% by weight to 50% by weight of one or more (meth) acrylic polymers (Pl) , and(a2) from 50% by weight to 90% by weight of one or more (meth) acrylic monomers (Ml) , each monomer (Ml) comprising only one (meth) acrylic function per monomer,(b) from 50 parts by weight to 150 parts by weight of composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) comprising :(bi) from 40% by weight to 80% by weight of one or more unsaturated polyesters (UP1) or a vinyl ester resin (VE1) , and(b2) from 20% by weight to 60% by weight of one or more monomers (M2) ,(c) optionally from 0.01 part by weight to 7 parts by weight of a polymerization initiator (INI1) ,(d) optionally between lOOppm and 20000ppm of an accelerator ii) polymerizing the liquid composition (LC1) that has impregnated the fibrous material, yields to a composite comprising a thermoset polymer, which can be recycled or easier recycled in comparison to a composite not comprising the (meth) acrylic composition (MCI) .

[0026] It has also been discovered a method (100) for recycling a composite comprising a thermoset polymer, based on polymerized liquid composition (LC1) , said process comprising the following steps :- optionally a step of cutting,- a step of grinding the thermoset polymer comprising composition or thermoset polymer comprising composite; yields to an easy process of recycling.[DETAILED DESCRIPTION]

[0027] According to a first aspect, the present invention relates to a liquid composition (LC1) comprising:(a) 100 parts by weight of a liquid (meth) acrylic composition(MCI) comprising:(ai) from 10% by weight to 50% by weight of one or more (meth) acrylic polymers (Pl) , and(a2) from 50% by weight to 90% by weight of one or more (meth) acrylic monomers (Ml) , each monomer (Ml) comprising only one (meth) acrylic function per monomer,(b) from 50 parts by weight to 150 parts by weight of composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) comprising:(bi) from 40% by weight to 80% by weight of one or more unsaturated polyesters (UP1) or a vinyl ester resin (VE1) , and (b2) from 20% by weight to 60% by weight of one or more monomers (M2 ) ,(c) optionally from 0.01 part by weight to 7 parts by weight of a polymerization initiator (INI1) ,(d) optionally between lOOppm and 20000ppm of an accelerator.

[0028] According to a second aspect, the present invention relates to a liquid composition (LC1) comprising:(a) 100 parts by weight of a liquid (meth) acrylic composition (MCI) comprising:(ai) from 10% by weight to 50% by weight of one or more(meth) acrylic polymers (Pl) , and(a2) from 50% by weight to 90% by weight of one or more(meth) acrylic monomers (Ml) , each monomer (Ml) comprising only one (meth) acrylic function per monomer,(b) from 50 parts by weight to 150 parts by weight of composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) comprising:(bi) from 40% by weight to 80% by weight of one or more unsaturated polyesters (UP1) or a vinyl ester resin (VE1) , and (bi) from 20% by weight to 60% by weight of one or more monomers (M2 ) ,(c) from 0.01 part by weight to 7 parts by weight of a polymerization initiator (INI1) ,(d) between lOOppm and 20000ppm of an accelerator.

[0029] According to a third aspect, the present invention relates to the use of a liquid composition (LC1) comprising:(a) 100 parts by weight of a liquid (meth) acrylic composition(MCI) comprising:(ai) from 10% by weight to 50% by weight of one or more(meth) acrylic polymers (Pl) , and(ai) from 50% by weight to 90% by weight of one or more(meth) acrylic monomers (Ml) , each monomer (Ml) comprising only one (meth) acrylic function per monomer,(b) from 50 parts by weight to 150 parts by weight of composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) comprising:(bi) from 40% by weight to 80% by weight of one or more unsaturated polyesters (UP1) or a vinyl ester resin (VE1) , and (bi) from 20% by weight to 60% by weight of one or more monomers (M2 ) ,(c) optionally from 0.01 part by weight to 7 parts by weight of a polymerization initiator (INI1) ,(d) optionally between lOOppm and 20000ppm of an accelerator, for preparing a recyclable polymeric composition or a recyclable polymeric article or a recyclable composite composition or a recyclable polymeric composite all comprising a thermoset polymer.

[0030] According to a fourth aspect, the present invention relates to the use of a liquid composition (LC1) comprising:(a) 100 parts by weight of a liquid (meth) acrylic composition (MCI) comprising:(ai) from 10% by weight to 50% by weight of one or more(meth) acrylic polymers (Pl) , and(a2) from 50% by weight to 90% by weight of one or more(meth) acrylic monomers (Ml) , each monomer (Ml) comprising only one (meth) acrylic function per monomer,(b) from 50 parts by weight to 150 parts by weight of composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) comprising:(bi) from 40% by weight to 80% by weight of one or more unsaturated polyesters (UP1) or a vinyl ester resin (VE1) , and(b2) from 20% by weight to 60% by weight of one or more monomers M2, each monomer M2 comprising only one polymerizable function per monomer,(c) from 0.01 part by weight to 7 parts by weight of a polymerization initiator (INTI) ,(d) between lOOppm and 20000ppm of an accelerator, for preparing a recyclable polymer composition or a recyclable polymeric article or a recyclable polymeric composite comprising a thermoset polymer.

[0031] According to a fifth aspect, the present invention relates to process for manufacturing composites by a process comprising the following steps : i) impregnating fibers or fibrous material with the liquid composition (LC1) according to the first or second aspect, ii) polymerizing the liquid composition (LC1) .

[0032] According to a sixth aspect, the present invention relates to a method (100) for recycling a thermoset polymer comprising composition (TPC) or thermoset polymer comprising composite (TPCO) obtained by polymerization of the liquid composition (LC1) according to the first or second aspect, said process comprising the following steps :- optionally a step of cutting,- a step of grinding the thermoset polymer comprising composition or thermoset polymer comprising composite.

[0033] The term "fibrous substrate" as used refers to several fibres, uni directional rovings or continuous filament mat, fabrics, felts or nonwovens that may be in the form of strips, laps, braids, locks or pieces .

[0034] The term " (meth) acrylic" as used refers to any type of acrylic or methacrylic monomer.

[0035] The term "PMMA" as used refers to homo- and copolymers of methyl methacrylate (MMA) , the weight ratio of MMA in the PMMA being at least 70 wt% for the MMA copolymer.

[0036] The term "monomer" as used refers to a molecule that can undergo polymerization .

[0037] The term "polymerization" as used refers to the process of converting a monomer or a mixture of monomers into a polymer .

[0038] The term "thermoplastic polymer" as used refers to a polymer that turns to a liquid or becomes more liquid or less viscous of soft when heated and that can take on new shapes by the application of heat and pressure . This applies also for slightly crosslinked thermoplastic polymers that can be thermoformed when heated above the softening temperature .

[0039] The term "thermoset polymer" as used refers to a polymer that has been obtained by hardening or curing ( extensive crosslinking ) a soft solid or viscous liquid prepolymer . The thermoset polymer alone cannot be melted for reshaping .

[0040] The term "polymer composite" as used refers to a multicomponent material comprising several different phase domains , among which at least one type of phase domain is a continuous phase and in which at least one component is a polymer .

[0041] The term "initiator" as used refers to a compound that can start / initiate the polymerization of a monomer or monomers .

[0042] By the abbreviation "phr" is meant weight parts per hundred parts of composition . For example Iphr of initiator in the composition means that 1 kg of initiator is added to 100kg of composition .

[0043] By the abbreviation "ppm" is meant weight parts per million parts of composition . For example lOO Oppm of a compound in the composition means that 0 . 1kg of compound is present in 100kg of composition .

[0044] By saying that a range from x to y in the present invention, it is meant that the upper and lower limit of this range are included, equivalent to at least x and up to y .

[0045] By saying that a range is between x and y in the present invention, it is meant that the upper and lower limit of this range are excluded, equivalent to more than x and less than y .

[0046] The liquid composition (LC1 ) according to the invention comprises at least a liquid (meth ) acrylic composition (MCI ) andcomposition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) .

[0047] According to a first preferred embodiment the liquid composition (LC1) comprises additionally a polymerization initiator (INI1) .

[0048] According to a second preferred embodiment the liquid composition (LC1) comprises additionally an accelerator.

[0049] According to a third preferred embodiment the liquid composition (LC1) comprises a thixotropy agent.

[0050] Preferably the viscosity or dynamic viscosity of the liquid composition (LC1) is in a range from 10 mPa*s to 10000 mPa*s, preferably from 20 mPa*s to 9000 mPa*s and advantageously from 30 mPa*s to 8000 mPa*s and more advantageously from 40 mPa*s to 7500 mPa*s and even more advantageously between 50mPa*s and 7000 mPa*s. The viscosity of the liquid composition (LC1) can be easily measured with a Rheometer or viscosimeter. The dynamic viscosity is measured at 25 °C. If the liquid (meth) acrylic syrup has a Newtonian behaviour, meaning no shear thinning, the dynamic viscosity is independent of the shearing in a rheometer or the speed of the mobile in a viscometer. If the liquid composition has a non-Newtonian behaviour, meaning shear thinning, the dynamic viscosity is measured at a shear rate of Is-1at 25°C.

[0051] The liquid composition (LC1) according to the invention, especially comprises at least a liquid (meth) acrylic composition (MCI) and a composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) .

[0052] The liquid composition (LC1) according to the invention comprises at least: a) 100 parts by weight of a liquid (meth) acrylic composition (MCI) comprising:(ai) from 10% by weight to 50% by weight of one or more(meth) acrylic polymers (Pl) , and(a2) from 50% by weight to 90% by weight of one or more(meth) acrylic monomers (Ml) , each monomer (Ml) comprising only one (meth) acrylic function per monomer,(b) from 50 parts by weight to 150 parts by weight of composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) comprising:(bi) from 40% by weight to 80% by weight of one or more unsaturated polyesters (UP1) or a vinyl ester resin (VE1) , and (bi) from 20% by weight to 60% by weight of one or more monomers(M2 ) .

[0053] As regards the liquid composition (LC1) of the invention it comprises between other components a (meth) acrylic monomer (Ml) and one or more monomers (M2) . Preferably the monomer (M2) is different from monomer (Ml) .

[0054] The quantity of the polymerization initiator (Inil) in the liquid composition (LC1) is at least O.Olphr relative to the sum of a liquid (meth) acrylic composition (MCI) and composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) . Preferably the quantity of polymerization initiator (Inil) in the composition is at least O.lphr, more preferably at least 0.2phr, even more preferably at least 0.3phr and advantageously at least 0.5phr relative to the sum of a liquid (meth) acrylic composition (MCI) and composition (C2) .

[0055] The quantity of polymerization initiator (Inil) in the composition (LC1) is at most 7phr relative to the sum of a liquid (meth) acrylic composition (MCI) and composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) . Preferably the quantity of either polymerization initiator (Inil) in the composition (LC1) is at most 6.5phr, more preferably at most 6phr, even more preferably at most 5.5phr and advantageously at most 5phr relative to the sum of a liquid (meth) acrylic composition (MCI) and composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) .

[0056] The quantity of polymerization initiator (Inil) in the composition is between O.Olphr and 7phr relative to the sum of a liquid (meth) acrylic composition (MCI) and composition (C2) comprising either an unsaturated polyester composition (UPC) or avinyl ester composition (VEC) . Preferably the quantity of either at least one initiator (Inil) in the composition is between 0. Iphr and 6.5phr, more preferably between 0.2phr and 6phr, even more preferably between 0.3phr and 5.5phr and advantageously between 0.5phr and 5phr relative to the sum of a liquid (meth) acrylic composition (MCI) and composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) .

[0057] As regards the (meth) acrylic monomer (Ml) of the liquid (meth) acrylic composition (MCI) , the monomer is chosen from acrylic acid, methacrylic acid, alkyl acrylic monomers, alkyl methacrylic monomers, hydroxyalkyl acrylic monomers and hydroxyalkyl methacrylic monomers, and mixtures thereof.

[0058] Preferably, the (meth) acrylic monomer (Ml) is chosen from acrylic acid, methacrylic acid, hydroxyalkyl acrylic monomers, hydroxyalkyl methacrylic monomers, alkyl acrylic monomers, alkyl methacrylic monomers and mixtures thereof, the alkyl group containing from 1 to 22 linear, branched or cyclic carbons; the alkyl group preferably containing from 1 to 12 linear, branched or cyclic carbons.

[0059] Advantageously, the (meth) acrylic monomer (Ml) is chosen from methyl methacrylate, ethyl methacrylate, methyl acrylate, ethyl acrylate, methacrylic acid, acrylic acid, n-butyl acrylate, isobutyl acrylate, n-butyl methacrylate, isobutyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, isobornyl acrylate, isobornyl methacrylate, hydroxyethyl acrylate and hydroxyethyl methacrylate, and mixtures thereof.

[0060] According to a preferred embodiment, at least 50% by weight and preferably at least 60% by weight of the (meth) acrylic monomer (Ml) is methyl methacrylate.

[0061] According to a first more preferred embodiment, at least 50% by weight, preferably at least 60% by weight, more preferably at least 70% by weight, advantageously at least 80% by weight and even more advantageously 90% by weight of the monomer (Ml) is methyl methacrylate or a mixture of methyl methacrylate with optionally at least one other monomer.

[0062] As regards the (meth) acrylic polymer (Pl) of the liquid (meth) acrylic composition (MCI) , mention may be made of polyalkyl methacrylates or polyalkyl acrylates . According to a preferred embodiment, the (meth) acrylic polymer is polymethyl methacrylate (PMMA) .

[0063] The term "PMMA" denotes a methyl methacrylate (MMA) homopolymer or copolymer or mixtures thereof.

[0064] According to one embodiment, the methyl methacrylate (MMA) homo- or copolymer comprises at least 70%, preferably at least 80%, advantageously at least 90% and more advantageously at least 95% by weight of methyl methacrylate.

[0065] According to another embodiment, the PMMA is a mixture of at least one homopolymer and at least one copolymer of MMA, or a mixture of at least two homopolymers or two copolymers of MMA with a different average molecular weight, or a mixture of at least two copolymers of MMA with a different monomer composition.

[0066] The copolymer of methyl methacrylate (MMA) comprises from 70% to 99.7% by weight of methyl methacrylate and from 0.3% to 30% by weight of at least one monomer containing at least one ethylenic unsaturation that can copolymerize with methyl methacrylate.

[0067] These monomers are well known and mention may be made especially of acrylic and methacrylic acids and alkyl (meth) acrylates in which the alkyl group contains from 1 to 12 carbon atoms. As examples, mention may be made of methyl acrylate and ethyl, butyl or 2-ethylhexyl (meth) acrylate . Preferably, the comonomer is an alkyl acrylate in which the alkyl group contains from 1 to 4 carbon atoms .

[0068] According to a first preferred embodiment, the copolymer of methyl methacrylate (MMA) comprises from 80% to 99.7%, advantageously from 90% to 99.7% and more advantageously from 90% to 99.5% by weight of methyl methacrylate and from 0.3% to 20%, advantageously from 0.3% to 10% and more advantageously from 0.5% to 10% by weight of at least one monomer containing at least one ethylenic unsaturation that can copolymerize with methyl methacrylate. Preferably, the comonomer is chosen from methyl acrylate and ethyl acrylate, and mixtures thereof.

[0069] The weight-average molecular mass of the (meth) acrylic polymer (Pl) should be relatively high, which means greater than 50 000 g / mol and preferably greater than 70 000 g / mol. According to a first more preferred embodiment, weight-average molecular mass of the (meth) acrylic polymer (Pl) the weight-average molecular mass of the (meth) acrylic polymer (Pl) is between 70 OOOg / mol and 500 OOOg / mol. According to a second more preferred embodiment, weightaverage molecular mass of the (meth) acrylic polymer (Pl) the weightaverage molecular mass of the (meth) acrylic polymer (Pl) is between 70 OOOg / mol and 250 OOOg / mol. According to a third more preferred embodiment, weight-average molecular mass of the (meth) acrylic polymer (Pl) the weight-average molecular mass of the (meth) acrylic polymer (Pl) is between 80 OOOg / mol and 250 OOOg / mol. According to a fourth more preferred embodiment, weight-average molecular mass of the (meth) acrylic polymer (Pl) the weight-average molecular mass of the (meth) acrylic polymer (Pl) is between 100 OOOg / mol and 250 OOOg / mol .

[0070] The weight-average molecular mass can be measured by size exclusion chromatography (SEC) .

[0071] The (meth) acrylic polymer is fully soluble in the (meth) acrylic monomer or in the mixture of (meth) acrylic monomers. It enables the viscosity of the (meth) acrylic monomer or the mixture of (meth) acrylic monomers to be increased. The solution obtained is generally called a "syrup" or "prepolymer". The dynamic viscosity value of the liquid (meth) acrylic syrup is between 10 mPa . s and 10 000 mPa.s. The viscosity of the syrup can be readily measured with a rheometer or a viscometer. The dynamic viscosity is measured at 25°C.

[0072] Advantageously, the liquid (meth) acrylic composition (MCI) contains no additional voluntarily added solvent.

[0073] The composition (C2) comprises either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) , or mixture.

[0074] According to a first preferred embodiment the composition (C2) comprises an unsaturated polyester composition (UPC) .

[0075] According to a second preferred embodiment the composition (C2) comprises a vinyl ester composition (VEC) .

[0076] According to a third preferred embodiment composition ( C2 ) comprises a mixture of an unsaturated polyester composition (UPC ) and a vinyl ester composition (VEC ) .

[0077] According to a fourth preferred embodiment the composition (C2 ) is an unsaturated polyester composition (UPC ) .

[0078] According to a fifth preferred embodiment the composition (C2 ) comprises is a vinyl ester composition (VEC ) .

[0079] With regard to the unsaturated polyester composition (UPC) of composition ( C2 ) , it is the precursor for a thermoset polymer .

[0080] The unsaturated polyester composition (UPC) comprises from 40% by weight to 80% by weight of one or more unsaturated polyesters (UP1 ) and from 20% by weight to 60% by weight of one or more monomers (M2 ) , each monomer (M2 ) comprising only one polymerizable function per monomer .

[0081] In a first preferred embodiment the unsaturated polyester composition (UPC ) comprises from 45 % by weight to 80% by weight of one or more unsaturated polyesters (UP1 ) and from 20% by weight to 55% by weight of one or more monomers (M2 ) .

[0082] In a second preferred embodiment the unsaturated polyester composition (UPC ) comprises from 40% by weight to 70% by weight of one or more unsaturated polyesters (UP1 ) and from 30% by weight to 60% by weight of one or more monomers (M2 ) .

[0083] In a third preferred embodiment the unsaturated polyester composition (UPC ) comprises from 40% by weight to 60% by weight of one or more unsaturated polyesters (UP1 ) and from 40% by weight to 60% by weight of one or more monomers (M2 ) .

[0084] The one or more unsaturated polyesters (UP1 ) are chosen from a condensation product of polyols with unsaturated and in some cases saturated dibasic acids or anhydrides . The polyols can be glycols as neopentyl glycol , ethylene glycol , 1 , 2 -propylene glycol and diethylene glycol ; but also glycerol , trimethylol propane or trimethylol propane mono allyl ether . The unsaturated dibasic acids or anhydrides can be maleic anhydride , fumaric acid or itaconic acid . The saturated dibasic acids or anhydrides can be phthalic anhydride , isophthalic acid, terephthalic acid adipic acid or sebacic acid .

[0085] Preferably the monomer (M2) is different from monomer (Ml) . The monomer (M2) can comprise only one polymerizable group per monomer, but also two polymerizable groups.

[0086] In a first more preferred embodiment the monomer (M2) with the unsaturated polyesters (UP1) is a vinyl monomer.

[0087] In a second more preferred embodiment the monomer (M2) with the unsaturated polyesters (UP1) is a vinyl aromatic containing monomer .

[0088] In a third more preferred embodiment the monomer (M2) with the unsaturated polyesters (UP1) is styrene.

[0089] In a fourth more preferred embodiment the monomer (M2) with the unsaturated polyesters (UP1) is an acrylic or methacrylic monomer or a diacrylic or dimethacrylic monomer.

[0090] In a fourth more preferred embodiment the monomer (M2) with the unsaturated polyesters (UP1) is an allyl monomer or diallyl monomer

[0091] With regard to the vinyl ester composition (VEC) of composition (C2) , it is the precursor for a thermoset polymer.

[0092] The vinyl ester composition (VEC) comprises from 40% by weight to 80% by weight of a vinyl ester resin (VE1) and from 20% by weight to 60% by weight of one or more monomers (M2) .

[0093] In a first preferred embodiment the vinyl ester composition (VEC) comprises from 45% by weight to 80% by weight of a vinyl ester resin (VE1) and from 55% by weight to 20% by weight of one or more monomers (M2) .

[0094] In a second preferred embodiment vinyl ester composition (VEC) comprises from 40% by weight to 70% by weight of a vinyl ester resin (VE1) and from 60% by weight to 30% by weight of one or more monomers (M2 ) .

[0095] In a third preferred embodiment vinyl ester composition (VEC) comprises from 40% by weight to 60% by weight of a vinyl ester resin (VE1) and from 60% by weight to 40% by weight of one or more monomers (M2 ) .

[0096] The vinyl ester resin (VE1) can be chosen from an addition product of an epoxide with an ethylenically unsaturatedmonocarboxylic acid. For example, by the reaction of a bisphenol-A glycidylether with methacrylic acid.

[0097] The epoxides could also be epoxy novolac or a cycloaliphatic epoxy or diepoxidized hydrogenated bisphenol A. The unsaturated acid could also be acrylic acid, crotonic acid or cinnamic acid.

[0098] Preferably the monomer (M2) is different from monomer (Ml) .

[0099] In a first more preferred embodiment the monomer (M2) with vinyl ester resin (VE1) is a vinyl monomer.

[0100] In a second more preferred embodiment the monomer (M2) with vinyl ester resin (VE1) is a styrene containing monomer.

[0101] In a third more preferred embodiment the monomer (M2) with vinyl ester resin (VE1) is styrene.

[0102] In a fourth more preferred embodiment the monomer (M2) with vinyl ester resin (VE1) is an acrylic or methacrylic monomer or a diacrylic or dimethacrylic monomer.

[0103] With regard to the polymerization initiator (Inil) , the initiators generate radicals that initiate the monomer (s) to start a radical polymerization of the monomer in order to form the polymer chains by propagation.

[0104] In a first preferable embodiment the initiator (Inil) is activated by heat .

[0105] In a second preferable embodiment the initiator (Inil) is activated by an activator or accelerator.

[0106] The to be activated initiator (Inil) is preferably radical initiators .

[0107] The radical initiator (Inil) can be chosen from peroxy group comprising compound or azo group comprising compounds and preferably from peroxy group comprising compound.

[0108] Preferably the peroxy group comprising compound comprises from 2 to 50 carbon atoms.

[0109] Preferably the peroxy group comprising compound is chosen from diacyl peroxides, peroxy esters, peroxydicarbonates, dialkyl peroxides, peroxyacetals, hydroperoxide, ketone peroxide or peroxyketale .

[0110] The initiator (Inil) can have a half-life time ti / 2 of 1 hour at a temperature between 40°C and 150°C.

[0111] In a first preferred embodiment the initiator (Inil) is chosen from a peroxydicarbonate.

[0112] In a second preferred embodiment the initiator (Inil) is chosen from a ketone peroxide.

[0113] In a third preferred embodiment the initiator (Inil) is chosen from a diacyl peroxide.

[0114] In a fourth preferred embodiment the initiator (Inil) is chosen from a peroxyketale .

[0115] In a fifth preferred embodiment the initiator (Inil) is chosen from a hydroperoxide .

[0116] Preferably the initiator (Inil) has a maximal storage temperature of 25 °C or less.

[0117] In order to conserve a dynamic viscosity of the liquid composition (LC1) , also that it allows good impregnation of the fibrous substrate if necessary, and to conserve the properties of the matrix obtained after polymerization of the fibrous substrate impregnated with liquid composition (LC1) , the components of the composition are incorporated in the following mass percentages: from 50 parts by weight to 150 parts by weight of composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) for 100 parts by weight of a liquid (meth) acrylic composition (MCI) .

[0118] In a first preferred embodiment the liquid composition (LC1) comprises from 50 parts by weight to 100 parts by weight of composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) for 100 parts by weight of a liquid (meth) acrylic composition (MCI) .

[0119] In a second preferred embodiment the liquid composition (LC1) comprises from 50 parts by weight to 80 parts by weight of composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) for 100 parts by weight of a liquid (meth) acrylic composition (MCI) .

[0120] In a third preferred embodiment the liquid composition (LC1) comprises from 80 parts by weight to 150 parts by weight of composition (C2) comprising either an unsaturated polyestercomposition (UPC) or a vinyl ester composition (VEC) for 100 parts by weight of a liquid (meth) acrylic composition (MCI)

[0121] Preferably the quantity of (meth) acrylic polymer (Pl) in the liquid composition (LC1) is chosen that it is at least 4wt% based on a composition comprising the four components (a2) (meth) acrylic monomers (Ml) , (ai) (meth) acrylic polymers (Pl) , (bi) unsaturated polyester (UP1) or a vinyl ester resin (VE1) and (b2) monomer (M2) .

[0122] More preferably the quantity of (meth) acrylic polymer (Pl) in the liquid composition (LC1) is chosen that it is at least 5wt% based on a composition comprising the four components (a2) (meth) acrylic monomers (Ml) , (ai) (meth) acrylic polymers (Pl) , (bi) unsaturated polyester (UP1) or a vinyl ester resin (VE1) and (b2) monomer (M2 ) .

[0123] In a first still more preferably embodiment, the quantity of (meth) acrylic polymer (Pl) in the liquid composition (LC1) is chosen that it is at least 7wt% based on a composition comprising the four components (a2) (meth) acrylic monomers (Ml) , (ai) (meth) acrylic polymers (Pl) , (bi) unsaturated polyester (UP1) or a vinyl ester resin (VE1) and (b2) monomer (M2) .

[0124] In a second still more preferably embodiment, the quantity of (meth) acrylic polymer (Pl) in the liquid composition (LC1) is chosen that it is at least 10wt% based on a composition comprising the four components (a2) (meth) acrylic monomers (Ml) , (ai) (meth) acrylic polymers (Pl) , (bi) unsaturated polyester (UP1) or a vinyl ester resin (VE1) and (b2) monomer (M2) .

[0125] In a third still more preferably embodiment, the quantity of (meth) acrylic polymer (Pl) in the liquid composition (LC1) is chosen that it is at least 12wt% based on a composition comprising the four components: (a2) (meth) acrylic monomers (Ml) , (ai) (meth) acrylic polymers (Pl) , (bi) unsaturated polyester (UP1) or a vinyl ester resin (VE1) and (b2) monomer (M2) .

[0126] In a fourth still more preferably embodiment, the quantity of (meth) acrylic polymer (Pl) in the liquid composition (LC1) is chosen that it is at least 15wt% based on a composition comprising the four components (a2) (meth) acrylic monomers (Ml) , (ai) (meth) acrylic polymers (Pl) , (bi) unsaturated polyesters (UP1) or a vinyl ester resin (VE1) and (b2) monomer (M2) .

[0127] The quantity of (meth) acrylic polymer (Pl) in the liquid composition (LC1) can be adapted by either changing the ratio of (meth) acrylic polymers (Pl) in the liquid (meth) acrylic composition (MCI) or by changing the ratio of the composition (C2) in the liquid composition (LC1) for a given liquid (meth) acrylic composition (MCI) .

[0128] The (meth) acrylic monomer (s) (Ml) in the liquid (meth) acrylic composition (MCI) are present in proportions of between 40% and 95% by weight, preferably between 40% and 90% by weight and advantageously between 45% and 85% by weight of the composition comprising (meth) acrylic monomer (s) (Ml) and (meth) acrylic polymer (Pl) •

[0129] The (meth) acrylic polymer (s) (Pl) in the liquid (meth) acrylic composition (MCI) are present in a proportion of at least 5% by weight, preferably at least 10% and advantageously at least 15% by weight of the composition comprising (meth) acrylic monomer (s) (Ml) and (meth) acrylic polymer (Pl) .

[0130] The (meth) acrylic polymer (s) (Pl) in the liquid (meth) acrylic composition (MCI) are present in a proportion of not more than 50% by weight, preferably not more than 40% and advantageously not more than 30% by weight of the composition comprising (meth) acrylic monomer(s) (Ml) and (meth) acrylic polymer (Pl) .

[0131] All the optional additives and fillers are added to the liquid (meth) acrylic composition (MCI) before the impregnation and or polymerization .

[0132] The liquid composition (LC1) according to the invention can comprise optionally as well activator or accelerator for polymerization .

[0133] The polymerization activator or accelerator can be chosen from tertiary amines such as N, N-dimethyl-p-toluidine (DMPT) , N,N- dihydroxyethyl-p-toluidine (DHEPT) , ethoxylated-p-toluidine (EPT) ; but also diethyl aniline (DEA) or dimethyl aniline (DMA) , organic- soluble transition metal catalysts or mixtures thereof.

[0134] The content or quantity of the activator with respect to the (meth) acrylic monomer (Ml) and the monomer (M2) of the liquidcomposition (LC1) is from lOOppm to 20000 ppm (by weight) , preferably from 200ppm to 10000 ppm by weight and advantageously from 300ppm to 7000 ppm.

[0135] The liquid composition (LC1) according to the invention can comprise optionally as well a thixotropic agent.

[0136] The thixotropic agent can be chosen from fumed silica, pyrogenic silica, glass microspheres, but also polyamides, polyurethanes and modified urea.

[0137] The content or quantity of the thixotropic agent is from 0.1 phr to lOphr in the the liquid composition (LC1) .

[0138] As regards the process for manufacturing the liquid (meth) acrylic composition (MCI) , a first step consists in preparing a first syrup comprising the (meth) acrylic monomer (Ml) or mixture of (meth) acrylic monomers and a (meth) acrylic polymer (Pl) .

[0139] Preferably the (meth) acrylic polymer (Pl) is added to the (meth) acrylic monomers and solubilized.

[0140] As regards the process for manufacturing the liquid composition (LC1) , a first step consists in mixing the liquid (meth) acrylic composition (MCI) and the composition (C2) in the respective ratios .

[0141] The optionally components are added afterwards.

[0142] The initiator (Inil) is added at last.

[0143] Preferably the initiator (Inil) is added at a temperature Tacjd below 50°C, more preferably below 40°C, advantageously below 30°C and more advantageously below 25°C.

[0144] ccording to another additional aspect, the current invention concerns process to prepare the liquid composition (LC1) comprising the following steps :(i) providing component (a) a liquid (meth) acrylic syrup comprising(ai) from 1% by weight to 50% by weight of one or more (meth) acrylic polymers Pl, and(a2) from 50% by weight to 99% by weight of one or more (meth) acrylic monomers Ml, each monomer Ml comprising only one (meth) acrylic function per monomer,(ii) adding for 100 parts of (a) from 50 to 150 parts by weight of component (b) , optionally component (c) from 0.01 part by weight to 7 parts by weight of a polymerization initiator (INI1) and optionally component (d) between lOOppm and 20 OOOppm of an accelerator,(iii) mixing the components (a) to (b) or (a) to (d) .

[0145] The liquid composition (LC1) according to the invention, as detailed in previous paragraphs, can be used for impregnating fibres or fibrous substrate or for manufacturing composite parts or composite material (CM1) , especially for preparing composites by resin transfer molding (RTM) , pultrusion, infusion, spray lay up or hand lay-up .

[0146] In a first preferred embodiment the use for impregnating fibres or fibrous substrate is spray lay-up.

[0147] In a second preferred embodiment the use for impregnating fibres or fibrous substrate is resin transfer molding.

[0148] In a third preferred embodiment the use for impregnating fibres or fibrous substrate is hand lay-up.

[0149] As regards the fibres or fibrous substrate, mention may be made of several fibres, uni directional rovings or continuous filament mat, fabrics, felts or nonwovens that may be in the form of strips, laps, braids, locks or pieces. The fibrous material may have various forms and dimensions, either one-dimensional, two- dimensional or three-dimensional. A fibrous substrate comprises an assembly of one or more fibres. When the fibres are continuous, their assembly forms fabrics.

[0150] The one-dimensional form corresponds to linear long fibres. The fibres may be discontinuous or continuous. The fibres may be arranged randomly or parallel to each other, in the form of a continuous filament. A fibre is defined by its aspect ratio, which is the ratio between the length and diameter of the fibre. The fibres used in the present invention are long fibres or continuousfibres. The fibres have an aspect ratio of at least 1000, preferably at least 1500, more preferably at least 2000, advantageously at least 3000 and more advantageously at least 5000, even more advantageously at least 6000, more advantageously still at least 7500 and most advantageously at least 10 000.

[0151] The two-dimensional form corresponds to nonwoven or woven fibrous mats or reinforcements or bundles of fibres, which may also be braided. Even if the two-dimensional form has a certain thickness and consequently in principle a third dimension, it is considered as two-dimensional according to the present invention.

[0152] The origins of the fibrous material may be natural or synthetic. As natural material one can mention plant fibres, wood fibres, animal fibres or mineral fibres.

[0153] Natural fibres are, for example, sisal, jute, hemp, flax, cotton, coconut fibres, and banana fibres. Animal fibres are, for example, wool or hair.

[0154] As synthetic material, mention may be made of polymeric fibres chosen from fibres of thermosetting polymers, of thermoplastic polymers or mixtures thereof.

[0155] The polymeric fibres may consist of polyamide (aliphatic or aromatic) , polyester, polyvinyl alcohol, polyolefins, polyurethanes, polyvinyl chloride, polyethylene, unsaturated polyesters, epoxy resins and vinyl esters.

[0156] The mineral fibres may also be chosen from glass fibres, especially of E, R or S2 type, carbon fibres, boron fibres, basalt fibres or silica fibres.

[0157] The fibrous substrate of the present invention is chosen from plant fibres, wood fibres, animal fibres, mineral fibres, synthetic polymeric fibres, glass fibres and carbon fibres, and mixtures thereof .

[0158] Preferably, the fibrous substrate is chosen from mineral fibres .

[0159] The fibres of the fibrous substrate have a diameter between 0.005 pm and 100 pm, preferably between 1 pm and 50 pm, more preferably between 5 pm and 30 pm and advantageously between 10 pm and 25 pm.

[0160] Preferably, the fibres of the fibrous substrate of the present invention are chosen from continuous fibres (meaning that the aspect ratio does not necessarily apply as for long fibres) for the one-dimensional form, or for long or continuous fibres for the two-dimensional or three-dimensional form of the fibrous substrate.

[0161] ccording to another additional aspect, the current invention concerns a polymeric composition (PCI) prepared by polymerization of the liquid composition (LC1) .

[0162] According to another additional aspect, the current invention concerns a thermoset polymer comprising composite (TPCO) comprising the polymerized liquid composition (LC1) .

[0163] ccording to another additional aspect, the current invention concerns an article or object or molded part or mechanical part made of composite material comprising the polymeric composition (PCI) or comprising the composite material (CM1) .

[0164] The liquid composition (LC1) is used for preparing a recyclable polymeric composition (PCI) or a polymeric article or a composite material (CM1) or a polymeric composite material all comprising a thermoset polymer or a thermoset polymer comprising composite (TPCO) thermoset polymer comprising composite (TPCO) .

[0165] The term recyclable applies for all these uses.

[0166] According to another additional aspect, the invention relates to a composite material (CM1) , a polymeric composite material comprising a polymeric matrix and a fibrous substrate of filler used as reinforcement, in which the fibrous substrate consists of long fibres, said composite material (CM1) being characterized in that the polymeric matrix is obtained after polymerization of said fibrous substrate impregnated with said liquid composition (LC1) according to the invention or liquid composition (LC1) according to the invention blended with filler.

[0167] According to another additional aspect, the invention relates to a process to prepare a polymeric composition (PCI) or acomposite material (CM1) , said process is comprising the following steps :(i) providing the liquid composition (LC1) ,(ii) optionally adding a filler (FI1) to the liquid composition (LC1) or impregnating fibres or fibrous substrate with the liquid composition (LC1) ,(iii) polymerizing the liquid composition (LC1) .

[0168] Another aspect of the present invention is a process for manufacturing composites or composite material (CM1) by a process comprising the following steps: i) impregnating fibers or fibrous substrate with the liquid composition (LC1) , and ii) polymerizing the liquid composition (LC1) .

[0169] In one embodiment the manufactured composites is thermoset polymer comprising composites (TPCO) .

[0170] The impregnation can be done by resin transfer molding (RTM) , pultrusion, infusion, spray lay up or hand lay-up.

[0171] A first preferred embodiment of the process for manufacturing composites or composite material (CM1) comprises impregnation by spray lay-up.

[0172] A second preferred embodiment of the process for manufacturing composites or composite material (CM1) comprises impregnation by resin transfer molding.

[0173] A third preferred embodiment of the process for manufacturing composites or composite material (CM1) comprises impregnation by hand lay-up .

[0174] The process can comprise an additional heating step.

[0175] The process can also comprise the additional steps of providing fibers and providing the liquid composition (LC1) .

[0176] To polymerize the liquid composition (LC1) means that the (meth) acrylic monomer (Ml) and the monomer (M2) of the liquid composition (LC1) are polymerized or copolymerized. This means as well to copolymerize with the unsaturated polyester (UP1) or the vinyl ester resin (VE1) , curing the precursor or prepolymer of the thermoset part, in order to establish a thermoset polymer.

[0177] In a first embodiment the (meth) acrylic monomer (Ml) and the monomer (M2) copolymerize with the unsaturated polyester (UP1) .

[0178] In a second embodiment the (meth) acrylic monomer (Ml) and the monomer (M2) copolymerize with the vinyl ester resin (VE1) .

[0179] In a third embodiment at least a part of the (meth) acrylic monomer (Ml) and at least a part of the monomer (M2) copolymerize with the unsaturated polyester (UP1) or the vinyl ester resin (VE1) .

[0180] The polymerization of the liquid composition (LC1) that has impregnated the fibers or fibrous substrate takes place at temperature between 0°C and 120°C, preferably between 10°C and 110°C. In a first preferred embodiment the temperature is between 10°C and 100°C, in a second preferred embodiment the temperature is between 10°C and 50°C and in a third preferred embodiment the temperature is between 50°C and 110°C.

[0181] If there is an activator or accelerator for polymerization, the temperature can be lower compared to the case when no activator or accelerator for polymerization is present in the liquid composition (LC1) .

[0182] If the viscosity of the liquid composition (LC1) at a given temperature is slightly too high for the impregnation process, it is possible to heat the syrup so as to have a more liquid syrup for sufficient wetting and correct and complete impregnation of the fibrous substrate.

[0183] During the polymerization step of the liquid composition (LC1) the conversion of the (meth) acrylic monomer (Ml) and the monomer (M2) of the liquid composition (LC1) that has impregnated the fibrous material is at least 80%, preferably 85%.

[0184] In a first preferred embodiment the conversion of the (meth) acrylic monomer (Ml) and the monomer (M2) of the liquid composition (LC1) is 90%.

[0185] In a second preferred embodiment the conversion of the (meth) acrylic monomer (Ml) and the monomer (M2) of the liquid composition (LC1) is 95%.

[0186] In a third preferred embodiment the conversion of the (meth) acrylic monomer (Ml) and the monomer (M2) of the liquid composition (LC1) is 98%.

[0187] In a fourth preferred embodiment the conversion of the (meth) acrylic monomer (Ml) and the monomer (M2) of the liquid composition (LC1) is 99%.

[0188] As regards the use of the mechanical parts made of composite material thus manufactured, mention may be made of many sectors and notably in the housing, motor vehicle, railway, sports, aeronautical industry, aerospace, photovoltaic or wind power sector, and in marine or nautical applications, medical applications as well as sport applications, energy applications, transport applications, storage application, construction and building applications, telecommunication applications.

[0189] The invention relates as well to an object obtained with liquid composition (LC1) or by the process or method.

[0190] The object is a mechanical part made of composite material or comprising composite material.

[0191] By way of example, in the housing sector, these materials may be used for making bathroom and / or kitchen equipment, such as countertops, kitchen sinks, bathroom sinks, shower trays, baths tubes or fascia panels.

[0192] The mechanical part made of composite material or or article or object or molded object or mechanical part made of composite material comprising the polymeric composition (PCI) prepared by polymerization of the liquid composition (LC1) , is especially a motor vehicle part, boat part, bus part, train part, sport article, plane or helicopter part, space ship or rocket part, photovoltaic module part, a material for construction or building for example composite rebars, dowels and stirrups for civil engineering and high rise construction, wind turbine part for example spar cap of girder of wind turbine blade, furniture part, construction or building part, telephone or cellphone part, computer or television part, or printer or photocopier part.

[0193] The mechanical part made of composite material is especially a piece of a nautical vehicle or a part of a wind turbine blade.

[0194] In a first preferred embodiment the mechanical part made of composite material is a part of a of a nautical vehicle.

[0195] In a second preferred embodiment the mechanical part made of composite material is a part of a wind turbine blade.

[0196] As regards the recycling method, it concerns the recycling a thermoset polymer comprising composition (TPC) or thermoset polymer comprising composite (TPCO) obtained by polymerization of the liquid composition (LC1) .

[0197] The method comprises optionally a step of cutting. This is necessary if the apparatus used for the grinding step, requires cutting to smaller pieces, or if the to be recycled composition or composite or article is too large for the grinding apparatus.

[0198] The grinding step reduces the to be recycled composition or composite or article with means of grinding apparatus. After the grinding step a ground composition (GC1) is obtained.

[0199] The ground composition (GC1) comprises the polymer composition obtained after polymerization of the liquid composition (LC1) and other added components. If a thermoset polymer comprising composite (TPCO) had been recycled, the ground composition (GC1) comprises parts of the fibrous substrate as well.

[0200] One of the advantages of the the liquid composition (LC1) to prepare the to be recycled thermoset polymer comprising composition (TPC) or thermoset polymer comprising composite (TPCO) obtained by polymerization of the liquid composition (LC1) , is that the obtained ground composition (GC1) after grinding step can be relatively coarse.

[0201] The ground composition (GC1) comprises grinded particles of different shape. There can be spherical particles, spherical particles, rod like particles, needle like particles, plate like particles, flaky particles, angular irregular particles.

[0202] By coarse is meant that there are grinded particles in the ground composition (GC1) that in one dimension are larger than 0.5 mm, preferably 1mm.

[0203] In one embodiment there are grinded particles in the ground composition (GC1) that in one dimension are larger than 2mm.

[0204] In another embodiment there are grinded particles in ground composition (GC1) that in one dimension are larger than 4mm.

[0205] In still another embodiment there are grinded particles in the ground composition (GC1) that in one dimension are larger than 6mm.

[0206] In still another embodiment there are 50% of grinded particles in the ground composition (GC1) that in one dimension are larger than 5mm.

[0207] The ground material can be evaluated by optical microscopy in order to evaluate the respective particle shapes and sizes.

[0208] The ground composition (GC1) can be reused for example by making new composite materials by thermocompression.[Methods ]

[0209] The weight-average molecular weight may be measured by size exclusion chromatography (SEC) . The chromatography column is calibrated with PMMA standards having a molecular weight between 402g / mol and 1 900 000 g / mol. The average molecular weight is expressed in g / mol for the number and average molecular weight Mn and Mw respectively. For the measurement, the concentration is Ig / L.

[0210] The viscosity of the liquid composition comprising at least the components a) and b) is measured with a Brookfield viscosimeter at 25 °C, according to ISO 2555:2018 "Plastics — Resins in the liquid state or as emulsions or dispersions — Determination of apparent viscosity using a single cylinder type rotational viscometer method". es]

[0211] A liquid composition is prepared by dissolving 30% by weight of the PMMA (BS520, a copolymer of MMA comprising ethyl acrylate as comonomer) as (Pl) in 70% by weight of methyl methacrylate as (Ml) , which is stabilized with HQME (hydroquinone monomethyl ether) .

[0212] To this lOOparts of liquid (meth) acrylic composition (MCI) are added 0.4phr by weight of N,N Dimethylaniline and Iphr Cobalt (II) 2-ethylhexanoate solution.

[0213] As composition (C2) an unsaturated polyester composition (UPC) is used: NORSYDYNE H 44382 TA from Polynt, having a viscosityof 440mPa*s (Brookfield LV2 at 50rpm) , comprising about 45wt% of styrene and 55wt% unsaturated polyester.

[0214] The liquid composition (LC1) is prepared by mixing the respective parts of liquid (meth) acrylic composition (MCI) and composition (C2) . The liquid composition (LC1) is finalized by adding 1.5 phr MEKP (Butanox M50 from Nouryon) .

[0215] Table 1 - compositions of liquid composition (LC1) in view of (MCI) and (C2)

[0216] As fibrous material a mat of glass fibers at 300gsm is used.

[0217] The impregnation of the fibrous material was made by hand lay-up .

[0218] The polymerization took place at about 20°C for about 1 hour.

[0219] Several fiber reinforced sheets with compositions according to table 1 were obtained.

[0220] For testing the recycling of the composite, the respective polymerized fiber reinforced sheets were pre-cut with a saw to pieces with approximate dimensions of 60mmx60mm.

[0221] Afterwards for the grinding a movable Granulator type ZM1 was used, having a chamber dimension of 180x150mm, using 6 rotor knives and 2 stationary knives .

[0222] Then the desired grid with holes of either 6mm, 12mm or 35mm holes was installed. The composite pieces were introduced. It was grinded for a couple of minutes at 20°C. The grinded material was recovered. Mainly the grid with 12mm was used.

[0223] The size of the grinded material was mainly above 1mm.

[0224] The grinded material was introduced in a mold . The mold was closed, slight pressure of about 5 bars applied, and put under a hot press at a temperature between 170 ° C-210 ° C and pressure between lOObar to 200 bars is applied, once the temperature has been attained, for 5 minutes . Afterwards it was cooled down to a temperature of about 50 ° C, the mold was recovered from the press and opened . The molded piece was unmolded and evaluated optically .

[0225] Evaluation is done by aspect , if the obtained molded piece is homogeneous with same surface aspect and if there are no dry spot .

[0226] The symbol means that the material is not at all homogeneous with same surface aspect and that here are many dry spots .

[0227] The symbol means that the material is not homogeneous with same surface aspect and that here are some dry spots .

[0228] The symbol "+" means that the material is homogeneous with same surface aspect and that here are no dry spots .

[0229] The symbol "++" means that the material is very homogeneous with same surface aspect and that here are no dry spots .

[0230] Table 2 - optical evaluation of respective molded pieces obtained from recycling

[0231] As can be seen in table 2 , the recycled molded products obtained after recycling of composite sheets comprising polymerized composition (LC1 ) of the invention, have a much better optical aspect and homogeneity .

Claims

CLAIMS1. A liquid composition (LC1) comprising:(a) 100 parts by weight of a liquid (meth) acrylic composition (MCI) comprising:(ai) from 10% by weight to 50% by weight of one or more (meth) acrylic polymers (Pl) , and(a2) from 50% by weight to 90% by weight of one or more (meth) acrylic monomers (Ml) , each monomer (Ml) comprising only one (meth) acrylic function per monomer,(b) from 50 parts by weight to 150 parts by weight of composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) comprising :(bi) from 40% by weight to 80% by weight of one or more unsaturated polyesters (UP1) or a vinyl ester resin (VE1) , and(b2) from 20% by weight to 60% by weight of one or more monomers (M2) ,(c) optionally from 0.01 part by weight to 7 parts by weight of a polymerization initiator (INI1) ,(d) optionally between lOOppm and 20000ppm of an accelerator,2. The liquid composition (LC1) according to claim 1, characterized in that it comprises,(c) from 0.01 part by weight to 7 parts by weight of a polymerization initiator.

3. The liquid composition (LC1) according to claim 1 or 2, characterized in that it comprises:(d) between lOOppm and 20000ppm of an accelerator.

4. The liquid composition (LC1) according to any of claims 1 to 3, characterized in that it comprises:(e) a thixotropy agent.

5. The liquid composition (LC1) according to according to any of claims 1 to 4, characterized in that the composition (C2) is an unsaturated polyester composition (UPC) .

6. The liquid composition (LC1) according to according to any of claims 1 to 4 , characterized in that the composition (C2) is a vinyl ester composition (VEC) .

7. The liquid composition (LC1) according to according to any of claims 1 to 6, characterized in that the liquid composition (LC1) comprises from 50 parts by weight to 100 parts by weight of composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) for 100 parts by weight of a liquid (meth) acrylic composition (MCI) .

8. The liquid composition (LC1) according to according to any of claims 1 to 6, characterized in that the liquid composition (LC1) comprises from 50 parts by weight to 80 parts by weight of composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) for 100 parts by weight of a liquid (meth) acrylic composition (MCI) .

9. The liquid composition (LC1) according to according to any of claims 1 to 6, characterized in that the liquid composition (LC1) comprises from 80 parts by weight to 150 parts by weight of composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) for 100 parts by weight of a liquid (meth) acrylic composition (MCI) .

10. The liquid composition (LC1) according to according to any of claims 1 to 9, characterized in that the quantity of (meth) acrylic polymer (Pl) in the liquid composition (LC1) is chosen that it is at least 4wt% based on a composition comprising the four components (a2) (meth) acrylic monomers (Ml) , (al) (meth) acrylic polymers (Pl) , (bl) unsaturated polyesters (UP1) or a vinyl ester resin (VE1) and (b2) monomer (M2) .

11. The liquid composition (LC1) according to according to any of claims 1 to 9, characterized in that the quantity of (meth) acrylic polymer (Pl) in the liquid composition (LC1) is chosen that it is at least 10wt% based on a composition comprising the four components (a2) (meth) acrylic monomers (Ml) , (al) (meth) acrylic polymers (Pl) , (bl) unsaturated polyesters (UP1) or a vinyl ester resin (VE1) and (b2) monomer (M2) .

12. The liquid composition (LC1) according to according to any of claims 1 to 11, characterized in that the (meth) acrylic monomer (Ml) is chosen from methyl methacrylate, ethyl methacrylate, methyl acrylate, ethyl acrylate, methacrylic acid, acrylic acid, n-butyl acrylate, isobutyl acrylate, n-butyl methacrylate, isobutyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, isobornyl acrylate, isobornyl methacrylate, hydroxyethyl acrylate and hydroxyethyl methacrylate, and mixtures thereof.

13. The liquid composition (LC1) according to according to any of claims 1 to 11, characterized in that at least 50% by weight and preferably at least 60% by weight of the (meth) acrylic monomer (Ml) is methyl methacrylate.

14. The liquid composition (LC1) according to according to any of claims 1 to 13, characterized in that the weight-average molecular mass of the (meth) acrylic polymer (Pl) is greater than 50 000 g / mol and preferably greater than 70 000 g / mol.

15. composition (LC1) according to according to any of claims 1 to 14, characterized in that the (meth) acrylic polymer (Pl) in the liquid (meth) acrylic composition (MCI) is present in a proportion of at least 15% by weight of the composition comprising (meth) acrylic monomer (s) (Ml) and (meth) acrylic polymer (Pl)16. The liquid composition (LC1) according to according to any of claims 1 to 14, characterized in that the quantity of (meth) acrylic polymer (Pl) in the liquid composition (LC1) ischosen that it is at least 10wt% based on a composition comprising the four components (a2) (meth) acrylic monomers (Ml) , (ai) (meth) acrylic polymers (Pl) , (bi) unsaturated polyester (UP1) or a vinyl ester resin (VE1) and (b2) monomer (M2) .

17. The liquid composition (LC1) according to according to any of claims 3 to 16, characterized in that the thixotropic agent is chosen from fumed silica, pyrogenic silica, glass microspheres, polyamides, polyurethanes and modified urea.

18. The liquid composition (LC1) according to according to any of claims 3 to 16, characterized in that the quantity of the thixotropic agent is from 0.1 phr to lOphr in the liquid composition (LC1)19. A process to prepare the liquid composition (LC1) according to any of claims 1 to 18, comprising the following steps:(i) providing component (a) a liquid (meth) acrylic syrup comprising(ai) from 1% by weight to 50% by weight of one or more (meth) acrylic polymers Pl, and(a2) from 50% by weight to 99% by weight of one or more (meth) acrylic monomers Ml, each monomer Ml comprising only one (meth) acrylic function per monomer,(ii) adding for 100 parts of (a) from 50 to 150 parts by weight of component (b) , optionally component (c) from 0.01 part by weight to 7 parts by weight of a polymerization initiator (INI1) and optionally component (d) between lOOppm and 20 OOOppm of an accelerator (iii) mixing the components (a) to (b) or (a) to (d) .

20. Use of the liquid composition (LC1) according to any of claims 1 to 18 to prepare a polymeric composition (PCI) .

21. Use of the liquid composition (LC1) according to any of claims1 to 18 for impregnating fibres or fibrous substrate.

22. Use of the liquid composition (LC1) according to any of claims 1 to 18 to prepare a composite material (CM1) .

23. Use of the liquid composition (LC1) according to any of claims 1 to 18 to prepare a recyclable polymeric composition or a recyclable polymeric article or a recyclable composite composition or a recyclable polymeric composite all comprising a thermoset polymer.

24. A polymeric composition (PCI) prepared by polymerization of the liquid composition (LC1) according to any of claims 1 to 18.

25. A process to prepare a polymeric composition (PCI) or a composite material (CM1) , said process is comprising the following steps:(i) providing the liquid composition (LC1) according to any of claims 1 to 18,(ii) optionally adding a filler (FI1) to the liquid composition (LC1) or impregnating fibres or fibrous substrate with the liquid composition (LC1) ,(iii) polymerizing the liquid composition (LC1) .

26. A process for manufacturing composites, preferably thermoset polymer comprising composites (TPCO) , said process comprising the following steps : i) impregnating fibres or a fibrous material with a liquid composition (LC1) comprising:(a) 100 parts by weight of a liquid (meth) acrylic composition (MCI) comprising:(ai) from 10% by weight to 50% by weight of one or more (meth) acrylic polymers (Pl) , and(a2) from 50% by weight to 90% by weight of one or more (meth) acrylic monomers (Ml) , each monomer (Ml) comprising only one (meth) acrylic function per monomer,(b) from 50 parts by weight to 150 parts by weight of composition (C2) comprising either an unsaturated polyester composition (UPC) or a vinyl ester composition (VEC) comprising :(bi) from 40% by weight to 80% by weight of one or more unsaturated polyesters (UP1) or a vinyl ester resin (VE1) , and(bi) from 20% by weight to 60% by weight of one or more monomers (M2) ,(c) optionally from 0.01 part by weight to 7 parts by weight of a polymerization initiator (INTI) ,(d) optionally between lOOppm and 20000ppm of an accelerator ii) polymerizing the liquid composition (LC1) .

27. The process according to claim 26, characterized in that impregnation is done by resin transfer molding (RTM) , pultrusion, infusion, spray lay up or hand lay-up.

28. The process according to claim 26, characterized in that impregnation is done by spray lay up or hand lay-up.

29. The process according to claim 26, characterized in that polymerization of the liquid composition (LC1) that has impregnated the fibers or fibrous substrate takes place at temperature between 0°C and 120 °C.

30. The process according to any of claims 26 to 29, characterized in that at least a part of the (meth) acrylic monomer (Ml) and at least a part of the monomer (M2) copolymerize with the unsaturated polyester (UP1) or the vinyl ester resin (VE1) .

31. A thermoset polymer comprising composite (TPCO) comprising the polymerized liquid composition (LC1) according to any of claims1 to 18.

32. An article or object or molded part or mechanical part made of composite material comprising the polymeric composition (PCI) according to claim 24 or comprising the composite material (CM1) prepared according to process of claim 25.

33. The article or object or molded object or mechanical part made of composite material according to claim 32 chosen from a motor vehicle part, boat part, bus part, train part, sport article,plane or helicopter part, space ship or rocket part, photovoltaic module part, a material for construction or building for example composite rebars, dowels and stirrups for civil engineering and high rise construction, wind turbine part for example spar cap of girder of wind turbine blade, furniture part, construction or building part, telephone or cellphone part, computer or television part, or printer or photocopier part.

34. A method for recycling a thermoset polymer comprising composition (TPC) or thermoset polymer comprising composite (TPCO) obtained by polymerization of the liquid composition (LC1) according to any of claims 1 to 18, said process comprising the following steps : optionally a step of cutting, a step of grinding the thermoset polymer comprising composition or thermoset polymer comprising composite.

35. The method according to claim 34, characterized in that grinding yields to ground composition (GC1) comprising grinded particles in the ground composition (GC1) that in one dimension are larger than 0.5 mm, preferably 1mm.

36. The method according to claim 34, characterized in that grinding yields to ground composition (GC1) comprising grinded particles in the ground composition (GC1) that in one dimension are larger than 4mm.

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